Small Intestinal Bacterial Overgrowth (SIBO)

Benjamin Wedro, MD, FACEP, FAAEM

Dr. Ben Wedro practices emergency medicine at Gundersen Clinic, a regional trauma center in La Crosse, Wisconsin. His background includes undergraduate and medical studies at the University of Alberta, a Family Practice internship at Queen's University in Kingston, Ontario and residency training in Emergency Medicine at the University of Oklahoma Health Sciences Center.

Bhupinder S. Anand, MBBS, MD, DPHIL (OXON)

Dr. Anand received MBBS degree from Medical College Amritsar, University of Punjab. He completed his Internal Medicine residency at the Postgraduate Institute of medical Education and Research, Chandigarh, India. He was trained in the field of Gastroenterology and obtained the DPhil degree. Dr. Anand is board-certified in Internal Medicine and Gastroenterology.

What causes SIBO?

The small intestine is a relatively clean place. The stomach receives food,
mixes it with acid and digestive juices and turns it into a clean slurry that is
pushed through the three parts of small intestine (duodenum, jejunum, ileum)
where the nutrients are absorbed into the body. The refuse is dumped into the
large intestine, or colon, where water is absorbed and the feces become more
solid and are eliminated from the body.

The normal bacteria (flora) of the gut, perform important functions, helping
to digest certain vitamins like folic acid and vitamin K, and they protect the
intestine from being invaded by disease causing bacteria. However, if the
normal function of the intestine is compromised, bacterial overgrowth may occur.
This may be the result of a lack of adequate stomach acid, damage to the intestine
by toxins like alcohol, or a decrease in the speed at which the small
intestine transfers material to the colon.

The colon is not as clean as the small intestine and reflux, or backflow, of
stool into the small intestine can colonize it with harmful bacteria.